Microchip Technology 24LC32A/P

Overview

24LC32A/P from Microchip Technology is a 32-Kbit I²C serial EEPROM organized as 4K × 8-bit memory, operating from 2.5V to 5.5V with 400 kHz max clock frequency, 5 ms max page write time, and hardware write-protect (WP) pin. It supports industrial (–40°C to +85°C) and extended (–40°C to +125°C) temperature ranges and is AEC-Q100 qualified for automotive use.

For engineers reviewing the 24LC32A/P datasheet, 24LC32A/P pinout, 24LC32A/P application, or 24LC32A/P equivalent, this device serves as a low-power, noise-immune nonvolatile memory for configuration storage, calibration data retention, and system parameter logging in embedded controllers, power supplies, and sensor modules.

Technical Context

The 24LC32A/P implements a two-wire I²C-compatible interface with Schmitt-trigger inputs and slope-controlled outputs to suppress ground bounce and improve noise immunity. Its internal address pointer enables current-address, random, and sequential read modes, while the 32-byte page buffer allows efficient burst writes within aligned 32-byte boundaries.

Write protection is enforced via the WP pin-tied to VCC to inhibit all array writes-or disabled when tied to VSS. Acknowledge polling is supported to detect write-cycle completion without fixed timing delays, enabling deterministic bus arbitration in multi-device systems.

Key Specifications

Pinout & Package

24LC32A/P is supplied in an 8-lead PDIP (Plastic Dual In-line Package) with 0.300-inch body width. Pin 1 is identified by a notch or dot; leads are tin-plated, lead-free (RoHS compliant), and rated for wave or reflow soldering per JEDEC J-STD-020.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar EEPROM applications.

Compared with AT24C32D-SSHM-T and BR24G32FJ-3GE2, the 24LC32A/P provides verified AEC-Q100 compliance, extended temperature support, and industry-standard PDIP packaging-making it the preferred choice for automotive and industrial designs where qualification and legacy footprint compatibility are mandatory.

Availability

24LC32A/P is available at Aetrix Electronics and suitable for industrial PLC configuration storage, automotive body control modules, medical device calibration data retention, and smart energy meter firmware settings requiring stable component supply across long production lifecycles.

Supply support for 24LC32A/P includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microchip Technology Inc. is a leading provider of microcontrollers, analog, FPGA, and memory solutions, serving industrial, automotive, and communications markets with vertically integrated design and manufacturing.

The 24LC32A/P belongs to Microchip's 24XX32A family of I²C EEPROMs, engineered for robust, low-power nonvolatile data storage in space-constrained, mission-critical embedded systems.

FAQ

What is the minimum V_CC required for reliable operation of the 24LC32A/P?

The 24LC32A/P requires a minimum V_CC of 2.5V for full functionality-including 400 kHz I²C operation and guaranteed write performance. Operation below 2.5V is not specified and may result in undefined behavior, failed writes, or incomplete acknowledge responses. Always maintain V_CC ≥ 2.5V in production designs using the 24LC32A/P.

Does the 24LC32A/P support page writes across address boundaries?

No. The 24LC32A/P restricts page writes to a single 32-byte physical page. If a write command crosses a 32-byte boundary (e.g., starting at address 0x001F and writing 4 bytes), data wraps to the start of the same page instead of advancing to the next. Application firmware must enforce alignment-ensuring all page writes begin at addresses divisible by 32-to prevent unintended overwrites in the 24LC32A/P.

How does the WP pin function during active write cycles in the 24LC32A/P?

The WP pin is sampled only at the Stop condition of each write command in the 24LC32A/P. Toggling WP during an ongoing internal write cycle has no effect-the operation completes as initiated. To prevent writes, WP must be held high before and during the entire I²C transaction, including the Stop bit. Once the write cycle begins, WP state changes are ignored until the next command.

Can multiple 24LC32A/P devices share the same I²C bus?

Yes. Up to eight 24LC32A/P devices can operate on a single I²C bus using unique hardware addresses set by A2, A1, and A0 pins. Each device responds only to its assigned 7-bit client address (1010 A2 A1 A0), enabling consolidated memory expansion up to 256 Kbits. Ensure pull-up resistors are sized for total bus capacitance-typically 2 kΩ for 400 kHz operation with ≤ 8 devices.

What is the purpose of acknowledge polling with the 24LC32A/P?

Acknowledge polling allows the host controller to detect write-cycle completion without fixed delays. After issuing a Stop condition, the host repeatedly sends a Start + write control byte (R/W = 0); the 24LC32A/P responds with ACK only after the internal 5 ms write cycle finishes. This method maximizes bus utilization and eliminates worst-case timing waits-especially valuable in time-sensitive real-time systems using the 24LC32A/P.